RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 96

• Manufacturer Part Number: RS8953
• Description: High-bit-rate Digital Subscriber Line (hdsl) Channel unit
• Manufacturer: Conexant Systems, Inc.

4.0 Registers
4.6 PCM Formatter
MF_LEN[5:0]
MF_CNT[5:0]
FRAME_LEN[8:0]
4-28
0xC7—PCM Multiframes per HDSL Frame (MF_CNT)
0xC8—PCM Frame Length (FRAME_LEN_LO)
0xC9—PCM Frame Length (FRAME_LEN_HI)
—
—
7
7
7
PCM Multiframe Length—Contains the number of PCM frames in one PCM multiframe, in
the range of 1 to 64 frames. A value of zero selects one frame per multiframe, which causes
TMSYNC and RMSYNC to operate at the PCM frame rate.
PCM Multiframes per HDSL Frame—Contains the number of PCM multiframes in one HDSL
6 ms frame, in the range of 1 to 64 multiframes. A value of zero selects one multiframe per
HDSL frame. MF_CNT operates in conjunction with FRAME_LEN and MF_LEN to create
transmit and receive PCM 6 ms timebases which are needed to perform transmit bit stuffing
and DPLL receive clock recovery. The RS8953B requires the product of MF_LEN and
MF_CNT to always equal 48 to match the number of HDSL payload blocks in an HDSL
frame. For example:
PCM Frame Length—Contains the number of bits in one PCM frame, in the range of 16 to
512 bits. A value of 255 selects 256 bit PCM frame length. The selected value includes
payload (number of timeslots x 8) and framing bits. For example, FRAME_LEN value equals
192 (0xC0) to select a 193-bit T1 frame.
—
—
6
6
6
—
5
5
5
Unframed = 1 frame
PCM Multiframe
ESF = 24 frames
SF = 12 frames
E1 =16 frames
—
4
4
4
FRAME_LEN[7:0]
Conexant
—
3
3
3
MF_CNT[5:0]
MF_LEN[5:0]
11 (0x0B)
15 (0x0F)
23 (0x17)
0 (0x00)
—
2
2
2
MF_CNT[5:0]
47 (0x2F)
2 (0x02)
3 (0x03)
1 (0x01)
RS8953B/8953SPB
—
1
1
1
HDSL Channel Unit
FRAME_LEN[8]
N8953BDSB
16 x 3 = 48
12 x 4 = 48
24 x 2 = 48
1 x 48 = 48
Product
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